ControllerSpecTest doesn't use OutPutMessagesField

[GalRogozinski]

          Notice that not only does none of the implemented tests define it but the spec test itself doesn't use it.

As I see it, the reason is that the controller spec test wants to test decided values and the decided messages for a list of instances (and not the instance's broadcasted messages).

I think that we should either drop this field or implement it in the tests if wanted.

Originally posted by @MatheusFranco99 in #484 (comment)